Manufacture of cyclic ddzihers



3O tween the water and the aldehyde. whilst propionaldehyde solutions of between 50 erable, as above indicated, that the solution 55 form f an aqueous; lutio nd, ay, for i glycol into a pressure resisting reaction vessel. 5

Patented Oct.12,1937 j 2,095,320 '1 UNITED STATES A E OFFIGE No Drawing. Application November 23, 1932, Se-

rial No. 644,082. In Great Britain November 30, 1931 2 Claims. (01. 260-54) This invention relates to the manufacture of stance, be supplied in vapour form in admixture cyclic diethers. with steam to a reaction liquor comprising the Compounds containing the carbonyl group, glycol and catalyst maintained at the desired such as aldehydes and ketones, react with polytemperature until all or the desired quantity of 5 hydric alcohols to produce cyclic: dioxides. For the glycol has been reacted upon. Alternatively, instance, as is described in my U. S. Application the aldehyde supplied to the reaction zone may, S. No. 644,081 filed November 23, 1932, formaldeif desired, contain only part or none at all of hyde reacts with ethylene glycol to produce eth-' the necessary water which may be present in ylene methylene dioxide and with higher glycols admixture with the glycol. Further, the aldeto produce the corresponding diethers of the hyde whether in admixture with Water or not, 10 higher glycols, and higher aldehydes, e. g. acetalmay be employed in the form. of a polymer, for dehyde, react with the glycols to produce higher instance a mixture of trioxy-methylene, ethylene alkylidene diethers, e. g. ethylidene diethers, of glycol, water and catalyst maybe heated to prothe glycols. duce ethylene methylene dioxide. According to the present invention the etheri- When the glycols or other polyhydric alcohols l5v fication of compounds containing the carbonyl are to be etherifled with keto-nes, the water may group, and in particular aldehydes, with aldelikewise be introduced by any of the methods hydes, glycols or other polyhydric alcohols is above indicated or in any other convenient effected, in an especially satisfactory manner, by manner. 1 carrying out the reaction in presence of restricted When aldehy es a e e p ye in t fo o 20 quantities of water, and particularly in presence aqueous solutions the concentration thereof may of about one molecule of water to each molecule vary considerably with the aldehyde to be em of the aldehyde or other body containing the carp fly u- With formaldehyde SOIutiOIlS, bonyl group. More particularly, aldehydes; are centrations of over formaldehyde may be 25 etheriied whilst in the form of highly concenemployed; very highly concentrated or saturated 25 trated aqueous solutions and preferably in the solutions, such as of about 48% to 52% formiorm of solutions containing not substantially aldehyde, are especially a a ou Aoeta more water than would be necessary to produce dehyde Solutions of between about and the hypothetical glycol by assumed reaction be- Strength ay advanta u y be mpl y d,

0 The etherification may be effected by means, about 70% and may advantageously be emor with the aid of, catalysts cap-able of promotployed. v ing etherification reactions, e. g. sulphuric acid, The production of the others is usually best hydrochloric acid, ferric chloride, zinc chloride, carried out at temperatures of between about phosphoric acid, benzene sulphonic acid, acid and C. in the case of aldehyde with alde- 35 salts such as alkali or other bisulphates or acid hyde etherification and 130 and C. in the phosphates. Such catalysts need not usually be case of aldehyde with glycol etherificaticn. mpl y d i a greater concentration a When the reactions are carried out at these temttlld it is p 'fl to 1 37 them not more peratures and in the liquid phase the presence 40 than 40% concentration. The useof concentraf the Hamel-may be maintained in any convem 40 tions of between 3 and 15% is p'a'rticulamly ient manner, e. g. by the use' of increased presvantageous; Sure The etnenfiqatwn of alvdehydes with glycqls or The following example illustrates the: produc- Other pglyhydnp alcoholsrma'y be effected slmply tion of ethylene methylene oxide in accordance I 45 by heating a mixture of the aldehyde, glycol and h t n but it t b d 45 catalyst containing the desired quantity of water with t e mven 1s 0 a un erwhich may be introduced by employing an aque- 9 that 131115 mple is given merely by way ous solutionof the aldehyde. When an aqueous of luustmmon and 1s m no Way solution of the aldehyde is employed it is pref- Example 50 i rtions of formaldehyde (in hould contain not substantially more water than Eqmmolecular prop) V is necessary to produce the h poth ti glycol the form of a 50% aqueous solution) and ethby assumed reaction with the aldehyde. The yleno glycol a mlxod a lotroduood t th r aldehyde need not however be employed in the with 12 parts of sulphuric acid per 100 parts of The reaction vessel is closed and heated to a temperature of about 140 C. for 4-5 hours.

After cooling, the reaction vessel is opened, unchanged aldehyde is removed from the reaction products by treatment with sodium hydrogen sulphite, sodium chloride is added to separate the water present as a lower layer and the upper layer, after being treated with sodium carbonate to remove acidity and dried by means of calcium chloride, is distilled to separate the ethylene methylene dioxide produced.

What I claim and desire to secure by Letters Patent is:

1. Process for the manufacture of ethylene methylene dioxide, which comprises subjecting formaldehyde to reaction with ethylene glycol in presence of water in amount equal to about 1 molecule per molecule of said formaldehyde.

2. Process for the manufacture of cyclic diethers, which comprises subjecting a lower aldehyde of the fatty acid series to reaction with a glycol in the presence of water in amount equal to about one molecule for each molecule of the 10 aldehyde.

HENRY DREYFUS. 

